Transdermal administration of therapeutic agents has many advantages, including convenience and gastrointestinal tract metabolism avoidance. But in the absence of penetration enhancing agents, many therapeutic agents are not capable of penetrating the skin in therapeutically effective concentrations. As such, compositions that facilitate the penetration of therapeutic agents through the skin are needed.
Also, the loss of skin moisture results in dry skin that can be uncomfortable, painful, or unattractive. Compositions that ameliorate dry skin and increase or maintain skin hydration are also needed.